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N<br />

Bz<br />

MeO2C OTBS<br />

214<br />

1-Benzoyl-2-(tert-butyl-dimethylsilyloxymethyl)-4-ethylidene-5-methyl-2,3,4,5-tetrahydro-<br />

1H-azepine-2-carboxylic acid methyl ester (214). Prepared by following general procedure M<br />

using: 75e (32 mg, 72 µmol). First portion <strong>of</strong> [Rh(CO)2Cl]2 (1.5 mg, 3.8 µmol) was added at rt<br />

°C. After 15 min at 90 °C another portion <strong>of</strong> [Rh(CO)2Cl] (3 mg, 7.6 µmol) was added and the<br />

reaction was heated to 90 °C for additional 2 h. Upon completion, the reaction mixture was<br />

purified by flash chromatography (pentanes-Et2O, 3 : 1, v/v) to afford 214 (23 mg, 72 %) as a 4 :<br />

1 mixture <strong>of</strong> diastereomers determined by 1 H NMR.<br />

214: (major diastereomer): 1 H NMR (CDCl3, 300MHz): δ 7.57-7.52 (m, 2H), 7.42-7.33 (m, 3H),<br />

5.89 (dd, J = 8.3, 2.6 Hz, 1H), 5.55 (q, J = 6.8 Hz, 1H), 4.83 (dd, J = 8.3, 3.9 Hz, 1H), 4.66 (d, J<br />

= 9.9 Hz, 1H), 3.89 (d, J = 9.9 Hz, 1H), 3.69 (s, 3H), 3.46 (bs, 1H), 3.04 (d, J = 14.9 Hz, 1H),<br />

2.64 (d, J = 14.8 Hz, 1H), 1.58 (d, J = 6.8 Hz, 3H), 1.19 (d, J = 7.2 Hz, 3H), 0.86 (s, 9H), 0.07 (s,<br />

3H), 0.03 (s, 3H): 13 C NMR (CDCl3, 75MHz): δ 171.5, 171.4, 136.2, 135.3, 130.4, 129.2, 128.6,<br />

128.0, 124.1, 121.9, 69.2, 64.6, 52.2, 37.8, 32.4, 25.8, 21.9, 18.0, 13.6, -5.3, -5.6; IR (thin film):<br />

ν 2953, 1734, 1641, 1342 cm -1 ; MS m/z (%) 443 (67), 428 (49), 413 (37), 386 (40), 105 (100);<br />

EI-HRMS calcd for C25H37NO4Si [M] + , m/z 443.2492; found 443.2500.<br />

235

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